Passivated Aluminum Nanohole Arrays for Label-Free Biosensing Applications

Abstract

We report the fabrication and performance of a surface plasmon resonance aluminum nanohole array refractometric biosensor. An aluminum surface passivation treatment based on oxygen plasma is developed in order to circumvent the undesired effects of oxidation and corrosion usually found in aluminum-based biosensors. Immersion tests in deionized water and device simulations are used to evaluate the effectiveness of the passivation process. A label-free bioassay based on biotin analysis through biotin-functionalized dextran-lipase conjugates immobilized on the biosensor-passivated surface in aqueous media is performed as a proof of concept to demonstrate the suitability of these nanostructured aluminum films for biosensing.

Integrated Collinear Refractive Index Sensor with Ge PIN Photodiodes

“…A comparison of our experimental results with experimental data from selected conventional, non-integrated plasmonic structures for refractive index sensing shows that the sensitivity in our setup is markedly higher than what can be observed for plasmonic Au nanoparticles 12 and, in particular, exceeds the sensitivities typically obtained in Al nanohole arrays 27 (see table 1). 28 700 647 Au nanocross 29 1400 500 Au nanopillar 30 1300 -1500 1000 Periodic array of Au mushrooms 31 1260 1010 Hybrid Au nanohole array 15 650 -700 670 Suspended NHA in Au film 32 795 717 Passivated Al NHA 27 700 -750 487 This work 1310 -1350 1180 When the device is incorporated into a microfluidic setup with a laser diode as the vertical illumination light source 33 , the operating wavelength λop is fixed. In this operating mode, a resonance peak shift induced by a change in nSup can be detected as a change in responsivity at λop.…”

Highly Sensitive Aluminum-Based Biosensors using Tailorable Fano Resonances in Capped Nanostructures

“…The quality factor (resonant wavelength/line width) of the system was 152 (473 nm/3.1 nm). The obtained FOM is higher than that of the previously reported FOM in nanostructure-based aluminum sensors1516174142, the FOM value (108) of the gold mushroom arrays11 and the theoretically estimated upper limits (FOM = 108) of the ATR-coupling SPR sensors43. We also tested the bulk sensitivity of capped nanoslits with different ridge height (H = 35) as shown in Fig.…”

Super Absorbing Ultraviolet Metasurface

“…nanoporous anodic alumina lithography [21]). Finally, in terms of potential oxidation issue of Al-based structures, it has been reported that ultrathin oxide protective layers on top of Al patterns may prevent further oxidation and corrosion and result in chemically stable biosensors [33]. Therefore, the proposed Al-based super absorber should be feasible for UV SERS applications with suitable surface protection treatment.…”